Submission #419737

#	Time	Username	Problem	Language	Result	Execution time	Memory
419737		Emin2004	Xylophone (JOI18_xylophone)	C++14	100 / 100	98 ms	444 KiB

xylophone

#include "xylophone.h"
#include <bits/stdc++.h>
using namespace std;

#define ll long long
#define pb push_back
#define pii pair<int, ll>
#define F first
#define S second

const int N = 100005;
const int mod = 1e9;

static int a[5005];
int found[N];

void solve(int n) {
    int l = 1, r = n;
    int pos = 1;
    for(int i = 4096; i > 0; i /= 2){
        if(pos + i >= n) continue;
        int x = query(pos + i, n);
        if(x + 1 == n) pos += i;
    }
   // answer(1, pos);
    a[pos] = 1;
    found[1] = 1;
    r = query(pos, pos + 1) + 1;
    a[pos + 1] = r;
    found[r] = 1;
    for(int i = pos + 2; i <= n; i++){
        int x = query(i - 1, i);
        int c1 = a[i - 1] - x;
        int c2 = a[i - 1] + x;
        if(c1 <= 0 || found[c1] == 1){
            a[i] = c2;
            found[c2] = 1;
        }
        else if(c2 > n || found[c2] == 1){
            a[i] = c1;
            found[c1] = 1;
        }
        else{
            int y = query(i - 2, i);
            if(max(abs(a[i - 1] - a[i - 2]), max(abs(a[i - 2] - c1), x)) == y){
                a[i] = c1;
                found[c1] = 1;
            }
            else{
                a[i] = c2;
                found[c2] = 1;
            }
        }
    }
    for(int i = pos - 1; i > 0; i--){
        int x = query(i, i + 1);
        int c1 = a[i + 1] - x;
        int c2 = a[i + 1] + x;
        if(c1 <= 0 || found[c1] == 1){
            a[i] = c2;
            found[c2] = 1;
        }
        else if(c2 > n || found[c2] == 1){
            a[i] = c1;
            found[c1] = 1;
        }
        else{
            int y = query(i, i + 2);
            if(max(abs(a[i + 1] - a[i + 2]), max(abs(a[i + 2] - c1), x)) == y){
                a[i] = c1;
                found[c1] = 1;
            }
            else{
                a[i] = c2;
                found[c2] = 1;
            }
        }
    }
	for(int i = 1; i <= n; i++) {
		answer(i, a[i]);
	}
}

Compilation message (stderr)

xylophone.cpp: In function 'void solve(int)':
xylophone.cpp:18:9: warning: unused variable 'l' [-Wunused-variable]
   18 |     int l = 1, r = n;
      |         ^

• Subtask 1: 11 / 11
• Subtask 2: 36 / 36
• Subtask 3: 53 / 53